wormhole-explorer/api/internal/cache/cache.go

56 lines
1.6 KiB
Go

// Package cache implement a simple cache redis client.
// It define a type [Cache] that represent the cache client and
// It define the methods Get to get a valur from a cache key.
package cache
import (
"context"
"errors"
"fmt"
"github.com/go-redis/redis/v8"
errs "github.com/wormhole-foundation/wormhole-explorer/api/internal/errors"
"go.uber.org/zap"
)
var ErrCacheNotEnabled = errors.New("CACHE NOT ENABLED")
// CacheClient redis cache client.
type CacheClient struct {
Client *redis.Client
Enabled bool
logger *zap.Logger
}
type CacheGetFunc func(ctx context.Context, key string) (string, error)
// NewCacheClient init a new cache client.
func NewCacheClient(url string, enabled bool, log *zap.Logger) *CacheClient {
client := redis.NewClient(
&redis.Options{
Addr: url,
})
return &CacheClient{Client: client, Enabled: enabled, logger: log}
}
// Get get a cache value or error from a key.
// If the cache is not enabled, the error value
// If the cache not contain a value from a key, the error value errors.ErrNotFound is returned.
// If exist some internal error in the cache, the error value errros.ErrInternalError is returned.
func (c *CacheClient) Get(ctx context.Context, key string) (string, error) {
if !c.Enabled {
return "", ErrCacheNotEnabled
}
value, err := c.Client.Get(ctx, key).Result()
if err != nil {
if err != redis.Nil {
requestID := fmt.Sprintf("%v", ctx.Value("requestid"))
c.logger.Error("ket does not exist in cache",
zap.Error(err), zap.String("key", key), zap.String("requestID", requestID))
return "", errs.ErrNotFound
}
return "", errs.ErrInternalError
}
return value, nil
}